In modern integrated circuits, the use of metal-insulator-metal (MIM) capacitor structures has become widespread in recent years. MIM capacitor structures can be used as capacitive elements in some implementations; and are formed in back-end-of-line (BEOL) processing, after front-end-of line (FEOL) processing has been completed. In other words, MIM capacitor structures are formed in or over metal interconnect layers that extend in horizontal planes over a semiconductor substrate in which active devices have been formed.
MIM capacitor structures are not limited to capacitor applications, however, and are also utilized for resistive random access memory (RRAM) devices. These RRAM devices include a variable resistance dielectric layer placed between top and bottom RRAM electrodes. The present disclosure relates to improved RRAM devices, as well as methods of making and operating such devices.